Image display apparatus, image forming apparatus, and non-transitory computer readable medium with distance-based image adjustment

ABSTRACT

An image display apparatus includes an image display that displays an image, and a change processing section that, if the image display is present in a user&#39;s gaze direction and if a distance between the user and the image display is shorter than a predetermined distance, performs a change process on the image displayed on the image display.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 fromJapanese Patent Application No. 2016-188477 filed Sep. 27, 2016.

BACKGROUND Technical Field

The present invention relates to an image display apparatus, an imageforming apparatus, and a non-transitory computer readable medium.

SUMMARY

According to an aspect of the invention, there is provided an imagedisplay apparatus including an image display that displays an image, anda change processing section that, if the image display is present in auser's gaze direction and if a distance between the user and the imagedisplay is shorter than a predetermined distance, performs a changeprocess on the image displayed on the image display.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiment of the present invention will be described indetail based on the following figures, wherein:

FIG. 1 is a diagram illustrating an exemplary configuration of an imageforming apparatus according to an exemplary embodiment;

FIG. 2 is an exemplary view obtained when the image forming apparatus isviewed from the front;

FIG. 3 is a block diagram illustrating an exemplary functionalconfiguration of a controller;

FIG. 4 is a diagram for describing an exemplary configuration of aline-of-sight detection sensor;

FIGS. 5A and 5B are diagrams for describing the exemplary configurationof the line-of-sight detection sensor;

FIG. 6 is a flowchart illustrating an exemplary procedure performed bythe image forming apparatus according to the exemplary embodiment; and

FIGS. 7A to 7D are diagrams for describing a specific example of theprocess performed by the image forming apparatus according to theexemplary embodiment.

DETAILED DESCRIPTION

Referring to the attached drawings, an exemplary embodiment of thepresent invention will be described in detail below.

Configuration of Image Forming Apparatus

The Configuration of an image forming apparatus 10 according to theexemplary embodiment will be described. FIG. 1 is a diagram illustratingan exemplary configuration of the image forming apparatus 10 accordingto the exemplary embodiment.

As illustrated in FIG. 1, the functional units that are included in theimage forming apparatus 10 according to the exemplary embodiment areconnected to a bus 101 and transmit/receive data via the bus 101.

A display 106, which serves as an exemplary image display, displaysvarious images about the image forming apparatus 10. For example, thedisplay 106 displays multiple options that are to be selected by a userwhen the user operates the image forming apparatus 10.

An operation receiving unit 107 receives operations from a user. Morespecifically, the operation receiving unit 107 receives user operationsperformed on information displayed on the display 106. For example, whenmultiple options are displayed on the display 106, the operationreceiving unit 107 receives user selection of an option.

The display 106 and the operation receiving unit 107 are formed by usinga touch panel display, and the operation receiving unit 107 and thedisplay 106 are disposed so that the operation receiving unit 107 issuperposed on the display 106. However, the operation receiving unit 107is not limited to one formed by using a touch panel display. Forexample, the operation receiving unit 107 may be formed by usingoperation buttons provided separately from the display 106 and apointing device such as a mouse.

An image reading unit 108 formed by using a so-called scanner apparatusreads an image on a document that has been set, and generates a readimage (image data) of the document.

An image forming unit 109, which serves as an exemplary image formingsection, uses, for example, an electrophotographic system to form atoner image according to image data, on a sheet of paper which isexemplary recording material. The image forming unit 109 may form animage by using another system such as an inkjet head system.

A communication unit 110 connected to a communication line (notillustrated) serves as a communication interface that communicates withother apparatuses connected to the communication line.

An image processor 111 performs image processing, such as colorcorrection and gradation correction, on an image represented by imagedata.

A human detection sensor 112 detects presence of a user in an areasurrounding the image forming apparatus 10, and determines the distancebetween the user who is present in the surrounding area and the imageforming apparatus 10. In other words, the human detection sensor 112functions as a ranging sensor that detects a user who is present aroundthe image forming apparatus 10 and that measures the distance betweenthe image forming apparatus 10 and the user. Examples of the humandetection sensor 112 include an infrared sensor and an ultrasonic wavesensor. Each of an infrared sensor and an ultrasonic wave sensor uses aphoto detector in the sensor to receive light, for example, that isemitted from a light source in the sensor onto a measurement target (auser in the exemplary embodiment) and that is reflected from the target.The received light is evaluated and converted into a distance so thatthe distance between the image forming apparatus 10 and the user ismeasured.

FIG. 2 is an exemplary view obtained when the image forming apparatus 10is viewed from the front. For example, as illustrated in FIG. 2, thehuman detection sensor 112 is disposed on the front of the image formingapparatus 10. In addition, the human detection sensor 112 is disposednear the display 106 of the image forming apparatus 10 (for example,beside the display 106), in other words, in an area defined in advancewith respect to the display 106. Therefore, the human detection sensor112 may be regarded as a unit that detects a user around the display 106and that measures the distance between the display 106 and the user.

A line-of-sight detection sensor 113 detects the line of sight of a userwho operates the image forming apparatus 10. As illustrated in FIG. 2,the line-of-sight detection sensor 113 is disposed on the front of theimage forming apparatus 10. In addition, similarly to the humandetection sensor 112, the line-of-sight detection sensor 113 is disposednear the display 106 of the image forming apparatus 10 (for example,beside the display 106), in other words, in an area defined in advancewith respect to the display 106.

In the exemplary embodiment, the human detection sensor 112 and theline-of-sight detection sensor 113 are separate sensors which aredisposed in respective different places. These sensors may be disposedtogether in one place.

A storage unit 105 is formed by using a storage device such as a harddisk device. For example, the storage unit 105 stores data received bythe communication unit 110 and also stores read images (image data)generated by the image reading unit 108.

A controller 60 controls the units of the image forming apparatus 10.The controller 60 includes a central processing unit (CPU) 102, a readonly memory (ROM) 103, and a random access memory (RAM) 104.

The ROM 103 is used to store programs executed by the CPU 102. The CPU102 reads programs stored in the ROM 103, and uses the RAM 104 as a workarea to execute the programs. The CPU 102 executes programs and therebycontrols the units of the image forming apparatus 10. Thus, for example,the image forming apparatus 10 forms an image on a sheet of paper andreads a document to generate a read image for the document.

Functional Configuration of Controller

The functional configuration of the controller 60 will be described.FIG. 3 is a block diagram illustrating an exemplary functionalconfiguration of the controller 60. The controller 60 includes auser-position determining unit 61, a user-position-information acquiringunit 62, a line-of-sight detecting unit 63, a user-action determiningunit 64, and a change processor 65.

On the basis of a detection result from the human detection sensor 112,the user-position determining unit 61 determines whether or not a useris present near the image forming apparatus 10 (display 106), in otherwords, within a predetermined distance from the image forming apparatus10 (display 106). In the description below, the predetermined distanceused in this determination may be referred to as a first distance.

When the user-position determining unit 61 determines that a user ispresent within the first distance from the image forming apparatus 10,the user-position-information acquiring unit 62 acquires information(hereinafter referred to as user position information) about thedistance between the user (for example, user's face) and the imageforming apparatus 10 (display 106), from the human detection sensor 112.

When the user-position determining unit 61 determines that a user ispresent within the first distance from the image forming apparatus 10,the line-of-sight detecting unit 63 obtains information (hereinafterreferred to as user's gaze information) about the direction in which theuser is gazing, from the line-of-sight detection sensor 113.

The user-action determining unit 64 determines a user's action on thebasis of the user position information obtained by theuser-position-information acquiring unit 62 and the user's gazeinformation obtained by the line-of-sight detecting unit 63. Morespecifically, in the determination of a user's action, the user-actiondetermining unit 64 determines whether or not the distance between theuser and the image forming apparatus 10 (display 106) is shorter than apredetermined distance while the state in which the display 106 ispresent in the user's gaze direction is maintained. The predetermineddistance used in this determination is a distance shorter than the firstdistance. In the description below, this predetermined distance may bereferred to as a second distance.

The second distance may be a fixed value for any user, or may bechanged, for example, in accordance with the height or the like of auser.

When the user-action determining unit 64 determines that the distancebetween the user and the image forming apparatus 10 (display 106) isshorter than the second distance while the state in which the display106 is present in the user's gaze direction is maintained, the changeprocessor 65, which serves as a change processing section, performs achange process on an image displayed on the display 106. An exemplarychange process is a process of enlarging a portion positioned in theuser's gaze direction (that is, a portion that is being viewed by theuser) in the image displayed on the display 106. In other words, theexemplary change process is a process of enlarging an area within acertain range which is positioned in the user's gaze direction. Thechange process is not limited to the enlargement process. For example, aprocess of scrolling a screen, a process of switching the entire screento another screen, and the like are exemplary change processes.

When the distance between the user and the image forming apparatus 10(display 106) is equal to or longer than the second distance, the changeprocessor 65 returns the image displayed on the display 106, to thestate before the change process. For example, when a portion positionedin the user's gaze direction has been enlarged, the portion is returnedback to the state before the enlargement.

The functional units that are included in the controller 60 and that areillustrated in FIG. 3 are implemented with software collaborating withhardware resources. Specifically, when the image forming apparatus 10 isimplemented by using the hardware configuration illustrated in FIG. 1,operating system (OS) programs and application programs which are storedin the ROM 103 are read onto the RAM 104 and the CPU 102 executes theprograms so that the functions, such as the user-position determiningunit 61, the user-position-information acquiring unit 62, theline-of-sight detecting unit 63, the user-action determining unit 64,and the change processor 65, are implemented.

Configuration of Line-of-Sight Detection Sensor

The configuration of the line-of-sight detection sensor 113 will bedescribed. FIG. 4 and FIGS. 5A and 5B are diagrams for describing anexemplary configuration of the line-of-sight detection sensor 113.

As illustrated in FIG. 4, the line-of-sight detecting unit 113 includesa light source 53 that emits infrared spot light to user's eyeball 56.The infrared light reflected from the eyeball 56 enters an optical lensset 54 via a fine aperture stop provided for an eyepiece 51. The opticallens set 54 causes the infrared reflected incident light to converge,for image formation, to a spot on the imaging surface of a chargecoupled device (CCD) 55. The CCD 55 converts, for output, a virtualimage (Purkinje image) that is formed on the imaging surface and that isproduced by the corneal reflection, into an electric signal.

As illustrated in FIGS. 5A and 5B, the virtual image is a virtual image72 that is produced by the corneal reflection in which the infraredlight emitted from the light source 53 is reflected at a pupil 71. Arelative positional relationship between the center of the pupil 71 andthe virtual image 72 changes proportionately with the rotation angle ofthe eyeball. In the exemplary embodiment, the electric signal whichindicates the virtual image and which is transmitted from the CCD 55 isused to perform image processing. On the basis of the result of theimage processing, the user's gaze direction is detected.

The method for detecting the user's gaze direction is not limited to themethod illustrated in FIGS. 4 to 5B. Another known method may be used.

As the line-of-sight detection sensor 113, for example, an eye trackeror the like produced by Tobii Technology, Inc. may be used.

Procedure Performed by Image Forming Apparatus

The procedure performed by the image forming apparatus 10 according tothe exemplary embodiment will be described. FIG. 6 is a flowchartillustrating an exemplary procedure performed by the image formingapparatus 10 according to the exemplary embodiment. The image formingapparatus 10 repeatedly performs the processes described in theflowchart in FIG. 6, at regular time intervals, such as every 100milliseconds.

The user-position determining unit 61 determines whether or not a useris present within the first distance from the image forming apparatus10, on the basis of the detection result from the human detection sensor112 (step 101). If a negative determination (No) is made in step 101,the process flow is ended. In contrast, if a positive determination(Yes) is made in step 101, the user-action determining unit 64 thendetermines whether or not the distance between the user and the display106 is shorter than the second distance while the state in which thedisplay 106 is present in the user's gaze direction is maintained, onthe basis of the user position information obtained by theuser-position-information acquiring unit 62 and the user's gazeinformation obtained by the line-of-sight detecting unit 63 (step 102).

If a positive determination (Yes) is made in step 102, the changeprocessor 65 performs the change process on an image displayed on thedisplay 106 (step 103). For example, the change processor 65 enlarges aportion positioned in the user's gaze direction.

Then, the user-action determining unit 64 determines whether or not thedistance between the user and the display 106 is equal to or longer thanthe second distance (step 104).

If a negative determination (No) is made in step 104, the user-actiondetermining unit 64 repeatedly performs the determination process instep 104. In contrast, if a positive determination (Yes) is made in step104, the change processor 65 returns the image displayed on the display106 back to the state before the change process (step 105). For example,if the change processor 65 has enlarged the portion positioned in theuser's gaze direction in step 103, the change processor 65 returns theimage back to the state before the enlargement. Then, the process flowis ended.

If a negative determination (No) is made in step 102, in other words, ifthe user-action determining unit 64 determines that the display 106 isnot present in the user's gaze direction or if the user-actiondetermining unit 64 determines that the distance between the user andthe display 106 is equal to or longer than the second distance (No instep 102), the process proceeds to step 101. In addition, in step 102,even if the distance between the user and the display 106 is shorterthan the second distance, when the display 106 is not present in theuser's gaze direction, a negative determination (No) is made. In thecourse of the change process on an image, if the user-action determiningunit 64 determines that the display 106 is not present in the user'sgaze direction or if the user-action determining unit 64 determines thatthe distance between the user and the display 106 is equal to or longerthan the second distance, the change processor 65 may stop (interrupt)the change process on an image.

A negative determination (No) is made in step 102, and the processproceeds to step 101. Then, if the user-position determining unit 61determines that a user is present within the first distance from theimage forming apparatus 10 (Yes in step 101), the user-actiondetermining unit 64 performs the determination process in step 102again. In contrast, if the user-position determining unit 61 determinesthat no users are present within the first distance from the imageforming apparatus 10 (No in step 101), the user has left an area nearthe image forming apparatus 10, and the process flow is ended.

As a case in which a user moves their face toward the display 106 toview an image on the display 106, the following exemplary cases may beconsidered: a case in which the user moves their face toward the display106 without directing their line of sight away from the display 106; anda case in which the user views, for example, an area around the display106 and temporarily redirects their line of sight. In addition, forexample, after the user moves their face toward the display 106 withoutviewing the display 106, the user may direct their line of sight to thedisplay 106 to view the display 106.

Therefore, in step 102, even when the line of sight of a user isdirected away from the display 106, if a certain condition is satisfied,the user-action determining unit 64 may make a positive determination(Yes).

For example, the user-action determining unit 64 measures a time forwhich the display 106 is present in the user's gaze direction, and alsomeasures a time for which the display 106 is not present in the user'sgaze direction. On the basis of the measured times, the user-actiondetermining unit 64 may determine whether or not the state in which thedisplay 106 is present in the user's gaze direction is maintained. Forexample, when a ratio of the time for which the display 106 is presentin the user's gaze direction with respect to the time for which thedisplay 106 is not present in the user's gaze direction is equal to orlarger than a predetermined threshold, even if the line of sight istemporarily directed away from the display 106, the user-actiondetermining unit 64 may determine that the state in which the display106 is present in the user's gaze direction is maintained.

For example, the user-action determining unit 64 may determine whetheror not the display 106 is present in the user's gaze direction and thedistance between the user and the display 106 is shorter than the seconddistance, without consideration of the user's gaze direction obtained inthe process in which the user approaches the display 106. If the display106 is present in the user's gaze direction and if the distance betweenthe user and the display 106 is shorter than the second distance, theuser-action determining unit 64 may make a positive determination (Yes)in step 102. In other words, if a state in which the display 106 ispresent in the user's gaze direction and in which the distance betweenthe user and the display 106 is shorter than the second distance iscontinuously maintained for a certain period, the user-actiondetermining unit 64 may make a positive determination (Yes). In such adetermination process, whether or not the change process on an image isto be performed may be determined on the basis of the user's gazedirection and the distance between the user and the display 106independently of how the user approaches the display 106.

Exemplary Process Performed by Image Forming Apparatus

An exemplary process performed by the image forming apparatus 10according to the exemplary embodiment will be described. FIGS. 7A to 7Dare diagrams for describing an exemplary process performed by the imageforming apparatus 10 according to the exemplary embodiment. In thedescription below, the change processor 65 performs the change processby enlarging a portion positioned in the user's gaze direction. Thesteps described below correspond to the steps in FIG. 6.

Assume that a user A approaches an area near the image forming apparatus10. As illustrated in FIG. 7A, the human detection sensor 112 detectspresence of a user around the image forming apparatus 10. On the basisof the detection result from the human detection sensor 112, theuser-position determining unit 61 determines whether or not a user ispresent within the first distance from the image forming apparatus 10(step 101).

When the user A approaches within the first distance from the imageforming apparatus 10, as illustrated in FIG. 7B, the human detectionsensor 112 measures the distance between the image forming apparatus 10and the user A. The line-of-sight detection sensor 113 detects the lineof sight of the user A. Then, the user-action determining unit 64determines whether or not the distance between the user A and thedisplay 106 is shorter than the second distance while the state in whichthe display 106 is present in the gaze direction of the user A ismaintained (step 102).

If the distance between the user A and the display 106 is shorter thanthe second distance while the state in which the display 106 is presentin the gaze direction of the user A is maintained (Yes in step 102), thechange processor 65 enlarges a portion positioned in the gaze directionof the user A (step 103). In the example in FIG. 7C, the changeprocessor 65 detects a portion indicated by a region 81 as the portionpositioned in the gaze direction of the user A. In this case, asillustrated in FIG. 7D, the change processor 65 enlarges the image inthe region 81 and displays the enlarged image on the display 106. Thus,a portion positioned in the gaze direction of the user A is enlarged sothat the portion that is being viewed by the user A is enlarged.Accordingly, the user A easily views the display on the display 106.

Another Exemplary Determination Process Performed by User-ActionDetermining Unit

Another exemplary determination process performed by the user-actiondetermining unit 64 will be described. In the above-described example,the user-action determining unit 64 determines whether or not thedistance between a user and the display 106 is shorter than the seconddistance. This configuration is not limiting. For example, theuser-action determining unit 64 may calculate a ratio of the currentdistance between a user and the display 106 with respect to the distance(hereinafter referred to as an initial distance) initially obtained whenthe user has stopped in front of the image forming apparatus 10 (infront of the display 106), so as to perform the determination process.In this case, the user-action determining unit 64 may be regarded as anexemplary grasping section.

More specifically, when the user stops in front of the display 106, inother words, when the user is present within the first distance from thedisplay 106 for a certain time, the user-action determining unit 64obtains information about the distance between the user and the display106 from the user-position-information acquiring unit 62. The obtaineddistance information is temporarily stored and held as the initialdistance, for example, in the RAM 104. After that, the user-actiondetermining unit 64 obtains information about the current distancebetween the user and the display 106 from the user-position-informationacquiring unit 62 at regular time intervals such as every 100milliseconds. Then, a ratio of the current distance to the initialdistance (=current distance/initial distance) is calculated.

The user-action determining unit 64 determines whether or not thecalculated ratio is less than a predetermined threshold (predeterminedratio) while the state in which the display 106 is present in the user'sgaze direction is maintained. If a positive determination (Yes) is madein this determination, like the case in which a positive determinationis made in step 102 in FIG. 6, the change processor 65 performs thechange process on an image. After that, when the calculated ratio isequal to or larger than the threshold, like the case in which a positivedetermination is made in step 104 in FIG. 6, the change processor 65returns the image back to the state before the change process.

Also in the determination process in this example, similarly to step 102in FIG. 6 which is described above, the user-action determining unit 64may make a positive determination (Yes) even when the line of sight isdirected away from the display 106 if the certain condition issatisfied.

More specifically, for example, the user-action determining unit 64 maymeasure the time for which the display 106 is present in the user's gazedirection, and may also measure the time for which the display 106 isnot present in the user's gaze direction. Then, the user-actiondetermining unit 64 may determine whether or not the state in which thedisplay 106 is present in the user's gaze direction has been maintained,on the basis of the measured times.

In addition, for example, if the display 106 is present in the user'sgaze direction and if a ratio of the current distance between the userand the display 106 with respect to the initial distance is less thanthe predetermined threshold, the user-action determining unit 64 maymake a positive determination (Yes). In other words, if the state inwhich the display 106 is present in the user's gaze direction and inwhich a ratio of the current distance between the user and the display106 with respect to the initial distance is less than the predeterminedthreshold is continuously maintained for a certain time, the user-actiondetermining unit 64 may make a positive determination (Yes).

As described above, the controller 60 of the image forming apparatus 10according to the exemplary embodiment determines whether or not thechange process is to be performed on an image, on the basis of theuser's gaze direction and the distance between the user and the imageforming apparatus 10 (display 106). Therefore, for example, when a userapproaches the display 106 without viewing the display 106 (having nointention of viewing the display 106), such as when the user bends downto open and close a paper-feed unit (paper tray) provided in a lowerportion of the image forming apparatus 10, the change process on animage is not performed as long as the user does not gaze the display 106after that.

Assume that the change process on an image is performed when a user doesnot view the display 106. For example, when the user views the display106 after that, the display has been already changed. Options other thanan option that is to be selected by the user may be enlarged or anoption that is to be selected by the user may disappear from thedisplay. Accordingly, through the process performed by the controller 60according to the exemplary embodiment, for example, in comparison with acase in which user's approach causes the change process on an image tobe performed even when the user approaches the display 106 withoutviewing the display 106, the change process on an image is performed inaccordance with the position and the line of sight of the user,achieving suppression of reduction in user operability.

In the exemplary embodiment, the description is made under theassumption that the second distance is a single value. However, thesecond distance may be set stepwise. In other words, multiple differentdistances may be provided as the second distance. In the case where thesecond distance is set stepwise, the change process on an image isperformed stepwise in accordance with the distance between a user andthe display 106. That is, in accordance with the distance between a userand the display 106, for example, an image is enlarged and displayedstepwise or a process of switching the entire screen to another screenis continuously performed.

In the exemplary embodiment, the controller 60, the display 106, and thelike are functional units related to display of an image. These may beregarded as functional units included in an image display apparatus.

As a matter of course, programs achieving the exemplary embodiment ofthe present invention may be provided by using a communication unit. Theprograms may be also provided by storing the programs in a recordingmedium such as a compact disc-read-only memory (CD-ROM).

The exemplary embodiment of the present invention is described above.The technical scope of the present invention is not limited to the scopedescribed in the exemplary embodiment. It is obvious from the claimsthat an embodiment obtained by making various changes and improvementson the exemplary embodiment is encompassed in the technical scope of thepresent invention.

What is claimed is:
 1. An image forming apparatus comprising: an imagedisplay that displays an image; one or more sensors that detect a user'spresence and detect a user's gaze direction; and a processor programmedto determine if the image display is present in the detected user's gazedirection and if a distance between the user and the image display isshorter than a predetermined distance, and in response to determiningboth that the image display is present in the detected user's gazedirection and that the distance between the user and the image displayis shorter than the predetermined distance, perform a change process onthe image displayed on the image display, wherein the change process isat least one of enlarging a portion of the image that is within theuser's gaze direction, scrolling the image, and replacing the image witha different image.
 2. The image forming apparatus according to claim 1,wherein, if the distance between the user and the image display isshorter than the predetermined distance while a state in which the imagedisplay is present in the user's gaze direction is maintained, theprocessor performs the change process on the image displayed on theimage display.
 3. The image forming apparatus according to claim 1,wherein the processor is programmed to grasp an initial distance betweenthe image display and the user, the initial distance being obtained whenthe user stands in front of the image display, wherein, if the imagedisplay is present in the user's gaze direction and if a ratio of adistance between the user and the image display with respect to theinitial distance is less than a predetermined threshold, the processorperforms the change process on the image displayed on the image display.4. The image forming apparatus according to claim 1, wherein theprocessor performs, as the change process, the enlarging of the portionof the image displayed on the image display, the portion beingpositioned in the user's gaze direction.
 5. The image forming apparatusaccording to claim 2, wherein the processor performs, as the changeprocess, the enlarging of the portion of the image displayed on theimage display, the portion being positioned in the user's gazedirection.
 6. The image forming apparatus according to claim 3, whereinthe processor performs, as the change process, the enlarging of theportion of the image displayed on the image display, the portion beingpositioned in the user's gaze direction.
 7. The image forming apparatusaccording to claim 1, further comprising an image forming section thatforms the image on recording material.
 8. A non-transitory computerreadable medium storing a program causing a computer to execute aprocess comprising: causing an image display to display an image;detecting a user's presence and detecting a user's gaze direction usingone or more sensors; determining if the image display is present in thedetected user's gaze direction and if a distance between the user andthe image display is shorter than a predetermined distance; and inresponse to determining both that the image display is present in thedetected user's gaze direction and that the distance between the userand the image display is shorter than the predetermined distance,performing a change process on the image displayed on the image display,wherein the change process is at least one of enlarging a portion of theimage that is within the user's gaze direction, scrolling the image, andreplacing the image with a different image.